The following description is provided to assist the understanding of the reader. None of the information provided or references cited is admitted to be prior art.
Nanoimprinting can generally refer to a process for forming a nanometer scale pattern on a substrate. A mold having one or more protuberances that form the pattern is pressed onto a resist (or resin) layer of the substrate at a predetermined pressure. In a thermal nanoimprint process, heat is applied to the resist layer to help form the pattern. In an optical (or radiation) nanoimprint process, radiation of a predetermined wavelength is applied to the resist layer to help form the pattern. After the pattern is formed, the mold is removed from the substrate and etching is performed as known to those of skill in the art. However, prior to etching the substrate, a residual layer is removed from the substrate.
The residual layer is comprised of portions of the resist layer that remain on the substrate at points of contact between the ends of the one or more protuberances that form the pattern and the substrate. If the residual layer is not removed, etching defects may occur during the etching process. Traditional nanoimprint processes remove the residual layer through a reactive ion etching process or through an ashing process that involves application of oxygen (O2) gas to the residual layer.